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56131L
18
Figure 26 - Installing Firestop
If area above is a living space, install
firestop below framed hole.
If area above is an attic, install firestop
above framed hole.
VENTING INSTALLATION
Continued
Flat Ceiling Installation
1. Cut a 12
1
/
2
" square hole in the ceiling us-
ing locating hole as a center point. Open-
ing should be framed to 12
1
/
2
" x 12
1
/
2
"
inside dimensions, as shown in Figure
18 on page 13, using framing lumber the
same size as ceiling joists. If area above
ceiling is an insulated ceiling or an attic,
nail firestop from top side. This prevents
loose insulation from falling into required
clearance space. If area above ceiling is a
living space, install firestop below framed
hole. The firestop should be installed with
no less than three nails per side (see
Figure 26).
2. Assemble desired lengths of pipe and
elbows necessary to reach from fireplace
flue up through firestop. Be sure all pipe
and elbow connections are fully twist-
locked (see Figure 17, page 14).
3. Cut a hole in roof using locating hole as
a center point. (Cover any exposed open
vent pipes before cutting hole in roof.) The
12
1
/
2
" x 12
1
/
2
" hole must be measured
on the horizontal, actual length may be
larger depending on pitch of roof. There
must be a 1" clearance from vent pipe to
combustible materials. Frame opening as
shown in Figure 18 on page 15.
4. Connect a section of pipe and extend
up through hole. If an offset is needed to
avoid obstructions, you must support vent
pipe every 3 feet. Use wall straps for this
purpose (see Figure 24, page 17). When
-
ever possible, use 45° elbows instead of
90° elbows. The 45° elbow offers less
restriction to the flow of flue gases and
intake air.
5. Place flashing over pipe section(s) ex
-
tending through roof. Apply a bead of
silicone or roof sealer to the bottom flange
of flashing and secure base of flashing
to roof and framing with roofing nails. Be
sure roofing material overlaps top edge of
flashing as shown in Figure 24, page 17.
There must be a 1" clearance from vent
pipe to combustible materials.
6. Continue to add pipe sections until the
height of vent cap meets the minimum
building code requirements described in
Figure 14, page 11.
Note: You must increase vent height for
steep roof pitches. Nearby trees, adjoining
rooflines, steep pitched roofs, and other
similar factors may cause poor draft or
down-draft condition (see Figure 24, page
17). Increasing vent height may solve this
problem.
7. Apply a bead of sealer to the upper edge
of flashing collar. Slide storm collar over
pipe and down to top edge of flashing.
Apply a second bead of silicone or roof
sealer around remaining seam of storm
collar. Twist-lock vent cap onto last section
of vent pipe. Finish sealing flange around
roofing material with roofing sealer.
Note: If vent pipe passes through any oc-
cupied areas above the first floor, including
storage spaces and closets, you must enclose
pipe. You may frame and sheetrock enclosure
with standard construction material. Make
sure and meet the minimum allowable clear-
ances to combustibles. Do not fill any required
air spaces with insulation.
